The association between time of birth and fetal injury resulting in death.

OBJECTIVE: In obstetrics, the care of patients in labor or with emergencies takes place day and night. Birth-related injury is among the worst of obstetric outcomes. This study sought to examine the relationship between time of birth and fetal injury resulting in death. STUDY DESIGN: The Birth-Related Neurologic Injury Compensation Association (NICA) is a Florida organization that pays for the care of infants >2500 g with birth-related brain or spinal cord injury resulting in permanent impairment. We conducted a case-control study using all deaths from the NICA database from 1989 to 2002. Data were collected on the antepartum, intrapartum, and postpartum care of the mother and fetus/child. Time of birth was identified for all cases and compared with a randomly selected control group of 1000 births in 1996 from Florida. RESULTS: Eighty deaths were identified in the NICA database of 447 total cases. Of the 80 cases, 36/80 (45%) were born from 11 pm to 8 am. Of the 999 controls (1 certificate sealed for adoption) 281 (28.1%) were born from 11 pm to 8 am. This yields an odds ratio of 2.09 (95% CI 1.29-3.40) for the association of nighttime birth with fetal injury resulting in death. CONCLUSION: Fetuses sustaining injuries resulting in death were more than twice as likely as controls to have been born from 11 pm to 8 am. Further studies are needed to determine the factors that affect this association and what changes might need to be made to optimize care regardless of time of day or night.

Lead precipitation by Vibrio harveyi: evidence for novel quorum-sensing interactions.

Three pleiotropic, quorum sensing-defective Vibrio harveyi mutants were observed to precipitate soluble Pb2+ as an insoluble compound. The compound was purified and subjected to X-ray diffraction and elemental analyses. These assays identified the precipitated compound as Pb9(PO4)6, an unusual and complex lead phosphate salt that is produced synthetically at temperatures of ca. 200 degrees C. Regulation of the precipitation phenotype was also examined. Introduction of a luxO::kan allele into one of the mutants abolished lead precipitation, indicating that the well-characterized autoinducer 1 (AI1)-AI2 quorum-sensing system can block lead precipitation in dense cell populations. Interestingly, the V. harveyi D1 mutant, a strain defective for secretion of both AI1 and AI2, was shown to be an effective trans inhibitor of lead precipitation. This suggests that a previously undescribed V. harveyi autoinducer, referred to as AI3, can also negatively regulate lead precipitation. Experiments with heterologous bacterial populations demonstrated that many different species are capable of trans regulating the V. harveyi lead precipitation phenotype. Moreover, one of the V. harveyi mutants in this study exhibited little or no response to intercellular signals from other V. harveyi inocula but was quite responsive to some of the heterologous bacteria. Based on these observations, we propose that V. harveyi carries at least one quorum sensor that is specifically dedicated to receiving cross-species communication.

New potential regulators of uterine leiomyomata from DNA arrays: the ionotropic glutamate receptor GluR2.

In the post-Genome era, new concepts emerge about the growth regulation of uterine leiomyomata. Screening of leiomyoma and myometrial tissues with DNA arrays revealed numerous genes up-regulated in leiomyomata that were not known to be expressed in the human uterus. GluR2, a subunit of a ligand-gated cation channel, is up-regulated in leiomyomata relative to myometrium by 15- to 30-fold at the protein and mRNA level and is localized in endothelial cells. GluR2 pre-mRNA in leiomyoma and myometrial tissues is nearly 100% edited at the Q/R site, indicative of low Ca(2+) permeability of the ion channels. In spontaneous leiomyomata in women or leiomyomata induced in the guinea pig model, there is a likely synergism linking increased production of estradiol and all-trans retinoic acid with up-regulation of nuclear receptor PPARgamma and RXRalpha proteins to support tumor growth. GluR2 might be coupled to this synergism directly or via interleukin-17B, kinesin KIF5 or related genes also up-regulated in leiomyomata. GluR antagonists should be tested as inhibitors of leiomyoma growth.

Effect of fundal pressure on maternal to fetal microtransfusion at the time of cesarean delivery.

AIM: To determine if fundal pressure at the time of cesarean delivery increases the amount of transplacental microtransfusion from mother to infant. METHODS: Pregnant women undergoing cesarean delivery were randomized to the standard uterine fundal pressure at the time of hysterotomy versus no fundal pressure. Babies of patients randomized to no fundal pressure were delivered with either vacuum or forceps. The proportion of placental alkaline phosphatase between maternal and cord blood was then determined and compared between the groups. RESULTS: Eighty-four women were randomized into two groups (44 in the pressure and 40 in the no pressure groups). There was no difference between the groups in demographic variables, or indications for cesarean. There was no difference in percentage of umbilical cord blood placental alkaline phosphatase between the pressure and no pressure groups (0.06 +/- 0.2 vs 10 +/- 0.29 IU, P = 0.43). CONCLUSIONS: Fundal pressure at the time of cesarean delivery does not increase the amount of transplacental microtransfusion, suggesting that modifying the method of cesarean would not decrease the chances of vertical transmission in HIV positive pregnant women.

Group B streptococcus: prevention of early-onset neonatal sepsis.

UNLABELLED: Group B streptococcus (GBS) was recognized as a major pathogen of neonatal disease in the 1970s. With a case-fatality rate of 5% to 20%, prevention of GBS neonatal disease has been an ongoing concern. The Centers for Disease Control and Prevention (CDC), and American College of Obstetricians and Gynecologists (ACOG) published guidelines for preventive strategies in 1996. These strategies, either a risk-based or a culture-based program, have been responsible for reduced incidence of GBS-newborn disease from 1.7 to 0.4 per 1,000 live births in the years 1993 to 1999. However, there has been considerable variability in practice patterns. Reanalysis now shows that a culture-based prevention strategy provides greater reduction in early-onset neonatal disease than a risk-based protocol. The CDC replacement guidelines of August 2002 recommend culture-based GBS prevention; the risk-based strategy is no longer supported. Continued efforts to eradicate GBS-newborn disease require an understanding of the pathogen, colonization, and transmission, GBS sampling and detection methods, and maternal therapy. Until a reliable vaccination against GBS is developed, prevention of neonatal GBS disease will rely upon intrapartum treatment of maternal carriers. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians LEARNING OBJECTIVES: After completion of this article, the reader will be able to define the pathogen, describe the methods of transmission and detection, and outline the current recommendations for maternal group B streptococcus therapy.

Dose variation that is associated with approximated one-quarter tablet doses of misoprostol.

OBJECTIVE: The purpose of this study was to evaluate dose variation in approximated one-quarter tablet misoprostol fragments. STUDY DESIGN: Misoprostol 100 microg tablets were weighed, separated into two lots, and quartered with a razor blade or a pill cutter. Fragments were reweighed, and the misoprostol content was determined by high-performance liquid chromatography mass spectroscopy. RESULTS: Fragment weights varied more when a pill cutter was used (P <.0001). Fewer pill-cutter fragments than razor-cut fragments weighed within 10% of expected (24% vs 65%, P <.0001). Misoprostol content among the fragments that were determined by high-performance liquid chromatography mass spectroscopy was 103% +/- 12% of expected (range, 73%-124%). Tablet fragments that weighed >or=27.5 mg contained misoprostol in excess of 110% of expected in seven of eight fragments, although none from fragments that weighed

Insights from gene arrays on the development and growth regulation of uterine leiomyomata.

OBJECTIVE: To use microarray analysis as an unbiased approach to identify genes involved in the induction and growth of uterine leiomyomata. DESIGN: Screen by arrays for up to 12,000 genes in leiomyoma (L) and control myometrium (M) from nine patients. SETTING: University research laboratories. PATIENT(S): Nine patients in the follicular and luteal phases of the menstrual cycle. INTERVENTION(S): mRNA from L and M was converted to biotin-labeled cRNA and hybridized to cDNA oligonucleotide sequences on the arrays. MAIN OUTCOME MEASURE(S): Greater than two-fold change in gene expression between leiomyoma and matched myometrium. RESULT(S): Prominent among the 67 genes overexpressed in L relative to M were dlk or Pref-1, doublecortin, JM27, ionotropic glutamate receptor subunit 2, apolipoprotein E3, IGF2, semaphorin F, myelin proteolipid protein, MEST, frizzled, CRABP II, stromelysin-3, and TGFbeta3. The genes dlk, IGF2, and MEST are paternally expressed imprinted genes, and the others are involved in tissue differentiation and growth. Prominent among the 78 genes down-regulated in L relative to M were alcohol dehydrogenases 1alpha-gamma, tryptase, dermatopontin, thrombospondin, coxsackievirus receptor, nur77, and c-kit. CONCLUSION(S): Arrays offer large-scale screening of mRNA expression, which will help us differentiate between the genes and metabolic pathways necessary for leiomyoma growth and those regulating myometrial contractions.

Buccal versus intravaginal misoprostol administration for cervical ripening.

OBJECTIVE: The purpose of this study was to compare the efficacy of misoprostol that is administered in the buccal pouch with the intravaginal route of administration. STUDY DESIGN: One hundred fifty-seven pregnant women with a singleton live gestation, Bishop score of <7, estimated fetal weight of <4500 g, and gestational age of >24 weeks were randomized to receive misoprostol that would be placed either in the buccal pouch or vagina every 6 hours. In the buccal group, after the first 2 doses of 200 microg, the dose was increased to 300 microg for the duration of the study (up to a total of 1600 microg). In the vaginal group, after the first 2 doses of 50 microg, the dose was increased to 100 microg for the duration of the study (up to a total of 500 microg). The primary outcome variable was the interval from the first dose to vaginal delivery. Power calculations indicated the need to enroll 71 patients in each arm of the study, which would allow for the detection of a 4-hour reduction in vaginal birth interval for buccal misoprostol. RESULTS: The hours from drug administration to vaginal delivery were similar between the buccal and vaginal groups (23.5 +/- 20.8 hours versus 21.3 +/- 13.4 hours), respectively. Thirty-five women (63%) versus 34 women (67%) delivered vaginally within 24 hours (P = not significant). The incidence of tachysystole was higher in the buccal group, 28 occurrences (38%) versus 15 occurrences (19%; P =.01). CONCLUSION: Buccal misoprostol is effective for cervical ripening but results in a higher incidence of tachysystole than does intravaginal administration.